In the prior art, a common liquid dispenser has been in the form of a reciprocable pump in which the plunger means has had an actuator portion at its upper end, the actuator portion being formed with a dispensing spout. By virtue of such structure, the plunger means may be depressed with one hand while the other hand receives the liquid. A spring returns the plunger. The pumping and receiving can be accomplished with one hand. Examples of such a pump dispenser are disclosed in the U.S. Pat. No. 3,064,310 which issued to R. C. Cooprider Nov. 20, 1962 and U.S. Pat. No. 3,180,534 which issued to O. H. Duda et al Apr. 27, 1965.
In order to assure the consumer that the contents of such dispensers are pristine at purchase and have not been partly used, contaminated or otherwise tampered with, tamper-evident covers or guards have been provided. In one version the guard has been in the form of an attachment to the top of such a dispenser. U.S. Pat. No. 4,424,919 which issued Jan. 10, 1984, to Knox et al discloses a dispenser having an attachment which hooks under an inward lip of a rotatable extension to the usual screw cap and bridges over the top of the actuator to hold it down. Tear lines are formed in the attachment so that a portion of the attachment can be torn away. The look of the torn attachment, still on the container, or if it is missing altogether, makes the tampering evident to the subsequent shopper.
The requirement of a special rotatable extension of Knox et al has, of course, meant an additional part which has had to be assembled onto the cap. In addition, it has sometimes been tricky to hook the clip under the ledge in a reliable manner.